A) \[20m{{s}^{-1}}\]
B) \[5m{{s}^{-1}}\]
C) \[15m{{s}^{-1}}\]
D) \[10m{{s}^{-1}}\]
Correct Answer: C
Solution :
[c] While moving downhill power \[\operatorname{P}=\left( w\,sin\theta +\frac{w}{20} \right)l0\] \[\operatorname{P}=\left( \frac{w}{10}+\frac{w}{20} \right)l0=\frac{3w}{2}\] \[\frac{P}{2}=\frac{3w}{4}=\left( \frac{w}{10}+\frac{w}{20} \right)V\] \[\frac{3}{4}=\frac{v}{20}\Rightarrow v=15m/s\] \[\therefore \] Speed of car while moving downhill\[v=15\text{ }m/s.\]You need to login to perform this action.
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